A fuel feed pump disclosed in JP-B2-H2-39638 includes a pump casing that receives a rotating member to pump fuel received in a fuel tank. The pump casing is press-inserted into a housing. When the outer circumferential periphery of the pump casing is entirely press-inserted into the housing, the pump casing receives radial force from the entire outer circumferential periphery, and the pump casing may be deformed. As a result, an internal clearance, which is formed between the pump casing and the rotating member, may decrease. In this case, when the rotating member contacts with the pump casing, rotation of the rotating member may be disturbed, and a pumping capacity of the fuel pump may decrease.
In view of the foregoing problems, it is an object of the present invention to produce a fuel feed pump, in which deformation of a pump casing received in a housing is reduced to produce a predetermined pumping capacity.
According to the present invention, a fuel pump includes a rotor, a rotating member, a pump portion, and a housing. The rotating member is rotated by the rotor. The rotating member generates suction force for drawing fuel. The pump portion includes a pump casing that receives the rotating member. The housing receives the rotor and the pump portion. The housing has an inner circumferential periphery that contacts with an outer circumferential periphery of the pump casing in an axial direction of the rotor to form a sealing portion, in which the housing and the pump casing are sealed therebetween. The inner circumferential periphery of the housing and the outer circumferential periphery of the pump casing form a gap in the radial direction of the housing on one of the side of the rotor and the opposite side as the rotor with respect to the sealing portion.
Alternatively, a fuel pump includes a rotor, a rotating member, a pump portion, and a housing. The rotating member is rotated by the rotor. The rotating member generates suction force for drawing fuel. The pump portion includes a pump casing that receives the rotating member. The housing receives the rotor and the pump portion. The housing has an inner circumferential periphery. The pump casing has an outer circumferential periphery. At least one of the inner circumferential periphery of the housing and the outer circumferential periphery of the pump casing has multiple protrusions that protrude in a substantially radial direction of the housing. The protrusions are arranged in a substantially circumferential direction of the housing. The protrusions are press-inserted into at least one of the inner circumferential periphery of the housing and the outer circumferential periphery of the pump casing.